GS700AT Series Smart Switch Software Administration Manual
Configuring Switching Settings 4-39
v1.0, March 2008
Layer 2 switching forwards Multicast packets to all relevant VLAN ports by default, treating the
packet as a Multicast transmission. Multicast traffic forwarding is functional. However, irrelevant
ports also receive the Multicast, causing increased network traffic. Multicast forwarding filters
enable forwarding of Layer 2 packets to port subsets, defined in the Multicast filter database.
The device supports forwarding L2 Multicast Packets. Multicast forwarding is enabled by default,
and not configurable by user.
The Multicast menu contains the following options:
• “Basic”
• “Advanced”
Basic
The Multicast Basic menu contains the following options:
• “IGMP Snooping Configuration”
IGMP Snooping Configuration
When IGMP snooping is enabled, all IGMP packets are forwarded to the CPU. The CPU analyzes
the incoming packets and determines which ports want to join which Multicast groups, which
ports have Multicast routers generating IGMP queries, and what routing protocols are forwarding
packets and Multicast traffic. A port requesting to join a specific Multicast group issues an IGMP
report specifying that Multicast group. This results in the creation of the Multicast filtering
database.